The present invention relates to a rotational speed controller for mixing equipment of a soil modifying machine and an engine speed controller for a soil modifying machine.
Recently, soil modifying machines for modifying soil at a site to reuse soil occurring during construction are often used. FIG. 8 shows a self-propelled soil modifying machine 1 as an example (for example, documents issued by Komatsu Ltd.). Soil, which is thrown into a raw soil hopper 16 by a loader such as a hydraulic shovel (not shown), is made to be of a predetermined thickness by a raking rotor 149 while being transported on a feed belt conveyor 130 and passes under a solidifying material hopper 2. When the soil is on the feed belt conveyor 130, a solidifying material feeder 148 is opened and solidifying materials are poured into the soil from the solidifying material hopper 2. The soil and the solidifying materials fall onto a discharge belt conveyor 150 while being cut and mixed with a soil cutter 147 serving as a rotating rotary cutting mixer provided in the vicinity of a conveyor outlet of the feed belt conveyor 130. When falling, grain diameters of soil covered with the solidifying materials become smaller by an impact of a rotary hammer 127 serving as a rotary impact mixer that is rotating. The soil mixed with the solidifying materials is transport outside the machine with the discharge belt conveyor 150. The soil modifying machine 1 moves between sites by traveling equipment 3. The oil cutter 147 and the rotary hammer 127 are each called a mixer, and two of them, collectively, are called mixing equipment.
However, the above soil modifying machine 1 has the following disadvantage. The soil cuter 147 and the rotary hammer 127 are driven by a hydraulic motor, and since a change-over valve for feeding pressure oil to the hydraulic motor is an on-off valve, for which a flow rate control cannot be performed, the rotational speed of the hydraulic motor is zero, or a predetermined value set in advance. Consequently, when a kind of earth to be modified is changed, a desired grain diameter of modified soil can hardly be obtained, and thus it is difficult to obtain quality of modified soil corresponding to a purpose of use.
Next, the self-propelled soil modifying machine 1 according to a prior art will be explained with FIG. 9A and FIG. 9B. Soil thrown into the raw soil hopper 16 by a loader such as a hydraulic shovel (not shown) is made to be of a predetermined thickness by a raking rotor 49 while being transported on a feed belt conveyor 30 and passed under the solidifying material hopper 2. When soil is on the feed belt conveyor 30, a solidifying material feeder 48 is opened and solidifying materials are poured into the soil from the solidifying hopper 2. The soil and the solidifying materials fall onto a discharge belt conveyor 50 while being cut and mixed with a soil cutter 47 provided in the vicinity of a conveyor outlet of the feed belt conveyor 30. When falling, a grain diameter of soil covered with the solidifying materials become smaller by an impact of a rotary hammers 27, 28 and 29. The soil mixed with the solidifying materials are transported outside the machine by the discharge belt conveyor 50. A crane 31 is used when the solidifying materials are replenished to the solidifying material hopper 2. The soil modifying machine 1 moves between sites by the traveling equipment 3.
The soil cutter 47 and the rotary hammers 27, 28 and 29 are collectively called a mixer. The feed belt conveyor 30, the crane 31, the solidifying material feeder 48, the raking rotor 49 and the discharge belt conveyor 50 are collectively called a standard working machine. As an optional working machine, included are an air compressor 53, which is used at a time of cleaning, a secondary and a tertiary belt conveyors 51 and 52 for transporting mixed soil to a place at a predetermined distance from the soil modifying machine 1, and a vibrating sieve 32 for further selecting finer soil from the mixed soil. The mixer, the standard working machine, the optional working machine, and the traveling equipment 3 are all driven by an engine 4.
However, the above soil modifying machine 1 has the following disadvantages. An operator selects the working machine to use from the mixer, the standard working machine and the optional working machine, and the operator performs a fine operation to set the working speed of an actuator of the working machine to use, for each soil and operation content. At this time, the operator performs an operation with the engine 4 always set at full throttle because it is troublesome to frequently adjust engine throttle according to the kind of the working machine to be operated and working speed. However, even when a small number of working machines are operated, and the required power is as small as in the case in which an operating speed is low, an engine speed is large, and thus causing the disadvantage of noise and vibration being large. In addition, there arises the disadvantage of fuel economy being poor.
The present invention is made in view of the above-described disadvantages, and its first object is to provide a rotational speed controller for mixing equipment of a soil modifying machine, by which optional quality of modified soil can be obtained. A second object of the present invention is to provide an engine speed controller for a soil modifying machine, which reduces noise and vibration of the engine and has excellent fuel economy.
In order to attain the above-described objects, the rotational speed controller for the mixing equipment of the soil modifying machine according to the present invention is a rotational speed controller for mixing equipment of a soil modifying machine for mixing and modifying soil to be modified, and has a constitution including
a mixer rotating to mix soil to be modified,
drive means for rotationally driving the mixer, speed control means for controlling rotational speed of the drive means based on an inputted rotational speed command value,
working mode setting means for outputting an working mode signal for setting a kind of soil to be modified, and
a controller for outputting the rotational speed command value corresponding to the working mode signal to the speed control means.
According to the above constitution, the kind of soil to be modified can be set by the working mode setting means, and therefore modified soil modified by the soil modifying machine always has a predetermined grain diameter. When only a degree of loosening soil to be modified is desired as quality of modified soil, the mixer is set at a lower rotational speed, and when modified soil with a fine grain diameter is desired, it is set at a higher rotational speed. Since the grain diameter of modified soil can be optionally set in this manner irrespective of the kind of soil to be modified, the rotational speed controller, by which quality corresponding to a use purpose can be selected, can be provided. Since the rotational speed of the mixer can be controlled according to the kind of soil to be modified and always driven at a necessary and sufficient rotational speed, abrasion speed of the mixer can be reduced and replacement cycle of the mixer becomes longer, thus operation cost can be reduced. Further, quality of modified soil can be set only by operating the working mode setting means, and therefor the soil modifying machine the operation of which is simplified and which has excellent operation feeling can be provided.
Further, in the rotational speed controller may have the constitution in which
a plurality of the mixers are included, and
the controller controls rotational speeds of a plurality of the mixers according to the rotational speed command values corresponding to the individual working mode signals of a plurality of the mixers.
According to the above constitution, a plurality of the mixers are included and the rotational speed is controlled according to each of the mixers, thus making it possible to set a grain diameter of modified soil minutely.
Further, in the rotational speed controller, the working mode setting means may have the constitution including a plurality of selection switches for setting the kind of soil to be modified.
According to the above constitution, the working mode setting means has a plurality of selection switches, and therefore a grain diameter of modified soil can be minutely obtained correspondingly to the operated selection switch.
Further, in the rotational speed controller, the controller may have the constitution in which it has a rotational speed table in which the individual rotational speed command values of a plurality of the mixers corresponding to a plurality of the selection switches are previously stored, and outputs the rotational speed command values, which are obtained from the rotational speed table correspondingly to any selected switch out of a plurality of the selection switches, to the speed control means.
According to the above constitution, in the rotational speed table, rotational speeds at which the quality of modified soil is confirmed by, for example, a test with the soil modifying machine, are set, and therefore the modified soil always and surely has a predetermined grain diameter.
Further, in the rotational speed controller, a plurality of the mixers may have the constitution in which they are a rotary cutting mixer for mixing soil to be modified with a cutter for cutting it, and a rotary impact mixer for mixing soil to be modified by giving it an impact with a hammer.
According to the above constitution, it has the rotary cutting mixer and the rotary impact mixer, and thus modified soil always and certainly has a predetermined grain diameter irrespective of the quality and grain diameter size of the soil to be modified.
A first aspect of an engine speed controller for a soil modifying machine according to the present invention, has a constitution including
mixers for mixing soil to be modified and working machines other than the mixers, which are provided at the soil modifying machine,
operation means for outputting operation signals to activate and deactivate at least the mixers of the soil modifying machine,
an engine for supplying driving power for at least the mixers of the soil modifying machine,
governor control means for controlling engine speed based on an inputted command value, and
a controller for outputting command values based on the operation signals to the governor control means.
According to the above constitution, the governor control means is controlled based on the operation signals outputted from the operation means for activating and deactivating the working machines of the soil modifying machine. Consequently, for example, during halts of the mixers of the soil modifying machine, the engine speed is set to be lower, and thus the engine speed controller for the soil modifying machine with noise and vibration being reduced with excellent fuel economy can be obtained.
A second aspect of the engine speed controller for the soil modifying machine according to the present invention has a constitution including
mixers for mixing soil to be modified and at least one of working machines for mixing around the mixers, which are provided at the soil modifying machine,
operation means for outputting operation signals to activate and deactivate the mixers and each of the working machines,
a pump having a plurality of hydraulic pumps for supplying pressure oil to each of a plurality of groups into which a plurality of hydraulic actuators driving the mixers and the working machines are divided, and driven by an engine,
governor control means for controlling engine speed based on an inputted command value, and
a controller for totaling pressure oil flow rates required by the hydraulic actuators operated based on the operation signals according to a plurality of the groups, computing a command value corresponding to engine speed according to a maximum required flow rate out of the totaled values, and outputting it to the governor control means.
According to the above constitution, based on the operation signals outputted from the operation means, the required flow rates of each of the groups are totaled, and the rotational speed of the engine for driving a plurality of hydraulic pumps for driving each of the groups is controlled according to the maximum value of a plurality of totaled values. As a result, each of the hydraulic pumps can secure the flow rate required by each of the groups, the mixers and the peripheral working machines which are to be operated can be surely operated. In addition, since the engine speed is controlled according to the kind of mixers and working machines to be operated, the engine speed controller for the soil modifying machine with noise and vibration being reduced with excellent fuel economy can be obtained.
Further, the engine speed controller may have the constitution including
working mode setting means for outputting an working mode signal for setting a kind of soil to be modified, and the constitution in which
the controller computes a command value to the governor control means according to the working mode signal and the operation signals, or when totaling required pressure oil flow rates according to a plurality of the groups, the controller totals them based on the working mode signal and the operation signals.
According to the above constitution, the operation speed of the mixers and the working machines is set according to the working mode signals and the operation signals set by the operator. As a result, the operation speed of the mixers and working machines to be operated, corresponding to the kind of soil to be modified, can be obtained, and thus the soil after modification can always obtain a predetermined fixed grain size and quality.
A third aspect of the engine speed controller for the soil modifying machine according to the present invention has a constitution including
mixers for mixing soil to be modified and at least one of working machines for mixing around the mixers, which are provided at the soil modifying machine,
operation means for outputting operation signals to activate and deactivate the mixers and each of the working machines,
a pump having a plurality of hydraulic pumps for supplying pressure oil to each of a plurality of groups into which a plurality of hydraulic actuators driving the mixers and the working machines are divided, and driven by an engine,
working mode setting means for outputting a working mode signal for setting a kind of soil to be modified,
governor control means for controlling engine speed based on an inputted command value, and
a controller for previously storing an engine control curve expressing relationship between discharge flow rates of a plurality of the hydraulic pumps and engine speed, and the constitution in which
the controller totals pressure oil flow rates required by the hydraulic actuators corresponding to the working mode signal and the operation signals according to a plurality of the groups, obtains engine speed corresponding to a maximum required flow rate out of the totaled values from the engine control curve, and outputs a command value corresponding to the obtained engine speed to the governor control means.
According to the above constitution, based on the engine control curve previously stored, the engine speed to be set is obtained from the required flow rates obtained according to the working mode signal and the operation signals. Since the engine control curve is the curve for which the performance is confirmed by the test of the actual soil modifying machine, the engine speed for securing the required flow rate can be surely obtained.
Further, in the engine speed controller, the working mode setting means may have the constitution in which it has a plurality of selection switches corresponding to the working mode signals.
According to the above constitution, the working mode setting means has a plurality of selection switches, and thus the kind of soil to be modified can be minutely set. Accordingly, the required flow rate can be minutely set, and the engine outputs only required speed, and therefore the engine speed controller for the soil modifying machine with noise and vibration being reduced with excellent fuel economy can be obtained.